Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (49권1호 26-31)

Electrochemical Characteristics under Cavitation-Erosion Environment of STS 304 and Hot-Dip Aluminized STS 304 in Sea Water Solution

천연해수 용액에서 STS 304와 용융 알루미늄 도금된 STS 304의 캐비테이션-침식 환경 하에서의 전기화학적 특성

정상옥;김성종;
Chong, Sang-Ok;Kim, Seong-Jong;

목포해양대학교 기관시스템공학부;
Division of Marine Engineering, Mokpo Maritime University;

DOI : 10.5695/JKISE.2016.49.1.26

Abstract

In this paper, the characteristics of a cavitation-erosion damage behavior on the STS 304 and hot-dip aluminized STS 304 under cavitation environment in sea water solution was investigated. The electrochemical experiments were carried out by potential measurement, anodic/cathodic polarization test, Tafel analysis, and also galvanostatic experiment in current density variables for the samples. The apparatus of cavitation-electrochemical experiment was manufactured in compliance with modified ASTM G-32 standard, with the conditions of sea water temperature of $25^{circ}C$ and the measurement, amplitude of $30{mu}m$. The damage behavior was analyzed by an observation of surface mophologies and a measurement of damage depth by a scanning electron microscope(SEM) and a 3D microscope, respectively, after electrochemical test. After polarization experiment under cavitation environment, much higher damage depths for the hot-dip aluminized STS 304 were observed comparing to the untreated STS 304. In addition, higher corrosion current density in hot-dip aluminized STS 304 presented than that of untreated STS 304 as a result of Tafel analysis.

Keywords

Cavitation;Hot-dip aluminized;Stainless steel;Sea water;Corrosion current density;